Shaking Table Testing on High-rise Buildings Considering Liquefiable Soil-structure Interaction

Shaking table model test was made on high-rise buildings with a consideration of the liquefiable soil-structure interaction with the saturated sand soil as model soil.A flexible container was fabricated to minimize the box effect.Macro-phenomena of high-rise building in ground of soil liquefaction due to natural earthquake were reproduced well.Test results show that the mode shape of the system is different from that of the structure on the fixed base in that there are rocking and swing at the foundation.The natural frequency of interaction system decreases and the damping ratio of soil increases with the increase of the shaking.The liquefied soil can filter and isolate vibration.Transient minus pore pressure occurs.Pore water pressure does not always dissipate in short time immediately after the excitations,but it may keep on increasing too.The distribution of the strain amplitude along the pile is the shape where the large strain is at the top of the pile and the small strain is at the tip of the pile.And the distribution of the contact pressure on the pile-soil interface is related to the excitation magnitude.